Activity all over the world has focused on the exploration of new synthetic routes to
newlineinorganic materials with improved properties. Chemical routes where homogeneity is
newlinerealized to an atomic scale, could give fine particles with uniform size distribution and
newlinelarge surface area. Recently new techniques such as low temperature initiated, self
newlinepropagating, gas producing combustion process, hydrothermal process and sol-gel
newlineprocess are developed for the synthesis of oxide materials. Synthesis of oxides
newlinenanoparticles is one of the major challenges in the development of advanced
newlinetechnologically important materials. By conventional solid state route, it is not
newlinepossible to obtain a nano-sized powder because due to the initial sizes of the reactants
newlinethey are very much larger. A major challenge encountered in the synthesis of
newlinenanocrystalline multicomponent oxides is the poor control of stoichiometry at the
newlinenano level. Although the solid state reaction is a simple process, this technique suffers
newlinefrom major draw backs like the weak reactivity of the starting materials and poor
newlinehomogeneity of the product.
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newlineNano-sized particles can be densified at much lower temperature as compared
newlineto large grained powders because of its high surface energy and driving force and the
newlinefinal product will exhibit unique mechanical, optical, magnetic and electrical
newlineproperties. Nanophosphors are being extensively investigated in last few years due to
newlinepotential applications in various types of displays such as plasma display panels, field
newlineemission displays. Conventional phosphors used in fluorescent lamps are not ideal for
newlinesolid state lighting because they have poor absorption for the light emitting diodes
newline(LED). Quantum dots exhibit narrow absorption and emission with a small Stoke
newlineshift. This behavior makes them useful in light management like up conversion and
newlinedown conversion.
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